The fierce competition that prevails in the present political and industrial scene has generated a need for controlling entry to large numbers of areas (through doors) by large numbers of authorized individuals. The problem is further exacerbated by the requirements that are unique to individual establishments, e.g., permitting only certain ones of an authorized group to enter certain areas, frequent recording of who entered a given area and when he entered, frequent turnover of a work force requiring security code changes, etc.
In response to these circumstances there has appeared on the market a number of security systems featuring the use of cards, push-buttons, dials etc., that activate locking systems and some of these systems include the use of linked printers that may be "plugged into" the lock to log entries, etc. For example, the DETEX Corp., of New Braunfels, Tex. offers an access control system for single doors that includes a combination keyboard-card access system to operate any one of five access modes, and the system can be hard wired into a printer which prints out entry data.
An approach to lock design that has been manufactured by Yale, Schlage, etc. for many years utilizes a key inserted into a key lock located in the shaft of an outside door handle. By turning the key, a barrel in the tubular shaft of the door handle is rotated. The end of the barrel facing the inside of the door is angled so that as the barrel rotates, a plunger engages the angled (or cam-like) end of the barrel and is forced to slide in the tubular shaft (outside spindle). The sliding plunger disengages from the door latch and unlocks the door. The other end of the plunger engages a spring loaded push button which projects from the tubular shaft (inside spindle) of the inside door handle. When it is desired to lock the door, the push button is pushed which forces the plunger back to the locking position.
An adaptation of this popular design has appeared on the market whereby the push-button has been replaced by a solenoid so that it can be operated by remote control. The use of a solenoid to replace the push-button has disadvantages, however, among which is its excessive use of power since the solenoid current must be maintained to hold the plunger open.
In summary, none of the systems of the prior art provide a compact self-contained construction that eliminates such inconveniences as high power drain, computer hookups, external wiring to add on components, extensive modification of the door, and versatility of programming that is featured in the present invention.